Speed reducer for aviation engines



Mar; 2o`

Filed Nov. l, 1921 2 sheets-sheet l K FUB Mar. 20, 1923 1,449,029 M., J, EL @ARBAROU SEEE@ MZDUQER FSR AVIATION ENGINES `Filed Nov. l, 1921 f l B j" Patented lll/lar. 2li, i923.

narran lrraras lSPEED FDR AVIATLON ENGINES.

Application filed November 1, 1921. Serial No. 512,143.

To all cli/0m 'it may concer/a.'

Be it known'that l, Memos JEAN Biir'rrsrii BAiuiAnoU, citizen of the French Republic, residing at Faris, in the Republic or France, have invented new ano useful improvements in Speer .Reducers for Aviation Engines, oi which the followingl is a specilicatioii.

This invention relatesto a speed-reducer for aviation engines of the type wherein the propeller' is centered upon a nose or sleeve situated in the axis of the cam shaft or the engine and having mounted thereon a gear wheel of large diameter which is driven by a pinion ot small diameter mounted upon the cranlr shaft. i

According to this invention, the gear wheel of large diameter which is'iinounted upon the nose or sleeve for driving the propeller is actuated by the pinion mounted on the crank shaft, through the intermediary of a pair of auxiliary gear wheels engaging the two first-mentioned gear wheels.

Each of the-said auxiliary gear wheels is rotatably mounted upon a iegulatingsleeve which is mounted in eccentric position on the support thereol and may be secured in anyv desired angular position in order to be able to adjust the engagement of the gears with great accuracy.

In case the said propeller is to be actuated by an engine of relatively high power, the above disposition, i. e. the use of two auxiliary gears will permitv ofreducin'g the pressure on the teeth and the molecular stress of the vmetal to a considerable degree without requiring the use' ol' gear wheels ol a great length. The undue lengthening or the gear wheels is observed to give rise to various drawbacks, in. that it requires a greater length and weight of the engine. On the other hand, an incre ysed length ot 'tooth will require a correspondingly greater accuracy in the machine worlr upon the teeth in order that the teeth shall roll properly upon each other. The smallest deviation from. the parallel position or any changes in shape which may arise for instance 'from the treatment of the steel will act to destroy theV eliect which it is proposed to obtain by the lengthening of the teeth, inasmuch as the latter are now caused to bear upon only a small portion of the length.

In cases where two auxiliary gear wheels are employed to obtain the driving action, it is necessary in order to secure the correct operation of both gear wheels that the amount of play between the interengaging gears may be properly adjusted for each of the said wheels. This conditioncis also obtained in the device according to the invention.

`ln the accompanying drawings given by way of example:

Fig-. 1 is a partial longitudinal section on the axis oi a speed reduction device for aviation. engines according to the invention.` lvFig. 2 is a cross-section` on the line X-X. *10' l l u Lv l. Fig. 3 is a horizontal section of the gear- I ing on the broken line Y Fig. 2.

Fig. is a vertical section on the line Z-Z, Fig. 5, of the device employed for mounting one of the auxiliary gear' wheels.

Fig. 5 is a section of the saine on the line V-V, Fig. 4.

6 is an elevation view, on the left hand side, corresponding to Fig. 5.

.As shown in the drawiing, the crankshaft a is provided with a toothed portion a" and terminates in a cylindrical extension where'- upon. is centered a pinion b. The: latter isv provided with an internal toothed portion engaging the teeth a and with'- an external' toothed portion of small diameter which serves to actuate the large-'diameter gear wheel 0. mounted upon ,a projecting sleeve or nose4 n forming an extension ofthe cam shaft a and actuating the propeller t. The latter isi'centered upon a sleeve which is concentric with the nose n and forms a part of a memberv L which is secured to the front face of the engine casing. j

According to this `invention, the pinion' o drives the gear wheel c through the intermediary of two auxiliary pinions D, E. Each of the latter pinions is mounted as shown in Figs. 3' to 5' upon a rsleeve A/ which is' slightly eccentric with reference' to the hollow supporting axle B.' The sleeve'A is provided at the exterior with'the gear teethv C. fWhen the sleeve A is turned about, the auxiliary gear wheels D and E are given an inward or outward movement to the amount which is considered necessary to properly engage the gear teeth. When the gearing has been suitably adjusted, the eccentric sleeve A is held in the lixed position by a disc plate K which is provided with teeth corresponding to those of the said sleeve and is maintained in place by the bolts F.

`This method. ot adjustment is sulhciently This latter geary wheel jc" isy sensitive to afford an adjustment between centers which is equal to l/lOO millimetre or less.

Each of the gear wheels D, E is mounted upon the respective sleeve A. by means of a pair of roller or ball bearings Gr and H disposed at the ends of the said gear wheel and outwardly of the toothed portion in order to permit of constructing,r the hub of the gear Wheel with a sutlicient thickness of metal under kthe teeth to withstandy the Stresses to which it is submitted for the driving action.

Should roller bearings be en'iployed, the gear wheel is maintained in position in the lengthwise sense by a thrust bearing` of variable shape and disposition. In F 3, thrust bearing I having' a single row of balls is used to` preventlengthwise more ment in either direction.y

.It is obvious that the said invention is not limited to the. details' of construction [which are hereinbefore set forth, these beincr given solely my way of example.

. aving now described my invention,what I claim as new and desire to secure by Letters Patent is:

l. A speed reducer for aviation engines comprisingan enginefraine, a crank shaft rotatably supported in said frame, a driv ing pinion of small diameter secured on said crank shaft, a cam shaft, a driven pinion of larger diameter on said cam shaft, two intermediate auxiliary gears engaging with the `said driving and driven pinions, a supporting nose secured to the engine frame and coaxial with the cam shaft, a propeller rotatably mounted on said nose, means for operatively connecting the cam shaft to the propeller and means for adjusting the distance between the said auxiliary gears on the one hand and the driving and driven pinions on the other hand.

2. A speed reducer for aviation engines comprising` an engine frame, a crank shaft rotatably7 supported in said frame, a drivingr pinion ofsmall diameter secured on rsaid crank shaft, a cam shaft, a driven pin ion of larger diameter on said cam shaft. tWO Aintermediate auxiliary gears engaging; with the said driving and driven pinions, a supporting nose secured to the engine frame and coaxial with the cam shaft, a propeller rotatably mounted on said nose, means for operatively connecting the cam shaft to the propeller, adjusting sleeves upon which the auxiliary gears are rotatably mounted, respectively, supporting spindles upon which said adjusting' sleeves are eccentrically and rotatably mounted and means for holding the adjusting sleeves in any desired angular position. j

3. A speed reducer for aviation engines comprising an engine frame, a crank shaft rotatably supported in said frame, a driving pinion of small diameter' secured on said crank shaft, a cam shaft, a driven pinion of larger diameter on said cam shaft, two intermediate auxiliary gears engaging with the said driving and driven pinions, a supporting nose secured to the engine frame and coaxial with the cam shaft, a propeller rotatablymounted on said nose, means for operatively connecting; the cam shaft to the propeller, two supporting' spindles, two adjusting sleeves eccentrically mounted and angularly adjustable on said supporting spindles, means for holding the adjusting sleeves in any desired angular position, and bearings mounted in the ends of the auxiliary gears laterally of the teeth thereof and supported on the adjusting sleeves.

4. A speed reducer for aviation engines comprising an engine frame, a crank shaft rotatably supported in said frame, a driving pinion of small diameter secured on said crank shaft, a cam shaft, a driven pinion of larger diameter on said cam shaft, two intermediate auxiliary gears engaging with the said driving and driven pinions, a supporting nose secured to the engine frame i and coaxial with the cam shaft, a propeller rotatably mounted on said nose, means .for operatively connecting the cam shaft to the propeller, two supporting spindles, two adjusting sleeves eccentrically mounted and regularly adjustable on said supporting spindles, means for holding the adjustingsleeves in any desired angular position` roller bearings mounted in the ends of the auxiliarv gears laterally to the teeth thereof and supported on the adjusting sleeves and an intermediate ball thrust bearing for pree venting` axial relative displacement between the auxiliary gear and the adjusting sleeve. In testimony whereof I have signed my name to this specification. y

MARIUS JEAN BAPTISTE BARBAROU. 

